Chemical methods of ceramic powder synthesis have been increasing in prominence in recent years because of their potential to produce homogeneous powders with controlled particle size and morphology. The majority of work using polymerized alkoxides has been done not for polycrystalline ceramics or powders but in silica or high silica glasses for optical fibre applications.
The principle behind sol-gel synthetic methods using polymerized alkoxides is basically a decomposition-recomposition reaction. Metal alkoxides (metal-organic precursors) are partially hydrolyzed or decomposed, then are recombined by polymerization or condensation to form a metal-oxygen-metal bond. An example of this technology is found in the use of aluminum isopropoxide to form alumina. Aluminum alkoxide is added to water with stirring, and hydrolysis begins. Typically a sol is stabilized by acid addition and heating, the solution then is gelled and fired to yield a solid alumina body.